US1980004A - Stepladder - Google Patents

Description

Nov. 6, 1934. A. A. scHRAMM STEPLADDER Filed Sept..- lO. 1930 5 Sheets-Sheet l 4 @l l j@ mani-KQ @mm wm NOV- 6, 1934 A. A. scHRAMM 1,980,004

STEPLADDER Filed Sept. l0 1930 3 Sheets-Sheet 2 Nov. 6, 1934. A. A. scHRAMM STEPLADDER Filed Sept. 10 1950 5 Sheets-Sheet 5 Patented Nov. 6, 1934 u y l UNITED STATES PATENT oFFicE STEPLADDER Albert A. Schramm, Chicago, lll. Application September 10, 1930, Serial No. 480,919 15 claims'. (o1. 22a-3s) This invention relates to ladders and is illusbase is bent over as indicated at 22 in Figure trated as embodied in a folding stepladder which 1. To further reinforce the top construction, is so constructed that the worker may have an and therefore the ladder as a whole, a metal bar unusually large step or platform on which to- 24 is passed across the top and rigidly fastened Work and may move the upper steps out of his to each side member as by the nuts 26. 60

Way. The front legs are properly spaced through The,ladder may conveniently include folding the rest of their length by the bottom step 28 cross-members or beams and a sliding sectional" and spacers 29. The back legs are reinforced platform which may be drawn out any desired bythe diagonal strips 30 and the U-shaped strips extent. V3l.v The latter extend along and are secured 65 One object of the invention is to provide a to the sides of the legs as at 32 to prevent them ladder which is safer than any heretofore known. from twisting.

Another object of the invention is to provide 'I'he proper spacing between front and back a folding ladder in which the steps are deep legs is secured by the folding beams, each of 16 enough to enable a user to have a full, firm and which has the two parts 34 and 36 hinged to- 70 shiftable footing thereon, as well as to stand getherfby hinge .38, which will permit the joint near the center of the ladder even when near to be` bent upwardly only. The beam parts 36 the bottom thereof to make the ladder less easily arepivoted to the front legs 10 as shown at 40, tipped over. and the beam parts 34 are pivoted at 42 to plates 2o Another object of the invention is to provide 44 which are riveted to back legs 12. 75 a ladder which the steps above the one being When the two beam members 34 and 36 are stood upon may be shifted out of the way, in operative position they form a continuous A further object of the invention is to prolevel beam as shown in Figure 1. The inside top vide a ladder which will be less tiresome to use. edges of these beams are cut away to form the Other objects of the invention will appear recess 46. 80 from the following description, drawings and Platforms are formed between the beams by claims. laying slats 48 in the recesses 46 to rest on the In the drawings, in which like numerals are bottom faces thereof. These slats are mounted used for similar parts throughouton leather straps 50 so that they may slideto- Figures 1 and 2 are vertical sectional views of gether along the beams. Of course, any other 35 the ladder in its operative and folded'positions flexible platform may be provided if desired. A respectively; retaining strip 51 is attached to project over the Figure 3 is a front elevation of the ladder; recess 46 to keep the slats in place. Sufficient Figure 4 is a plan view' of the top of the tolerance is left to insure easy movement of the a5 ladder; slats. As illustrated, the platforms preferably 90 Figure 5 is a detail sectional View showing one.. have a depth, i. e., a front to back width, greater of the sliding platform steps and connecting than the length of a mans shoe, to'permit the parts; user to stand or'turn around on it with ease and Figure 6 is a horizontal section of the detail safety. shown in Figure 5, taken along the line 6 6 The front slat 48 is provided with suitable re- 95 v of Figure 5; ,y inforcing means, 52 since it may occasionally be Figure 'I is a detail vertical section takenmalong subjected to abnormal Weights. The member 52 the line 7--7 of Figure 5; and also serves as a handle. There may be provided Figure 8 is a fragmentary view, similar to a suitable catch foi-'holding the platform inthe 4g Figure 1, but of a modification. desired position.n This catch, as illustrated, com- 100 -Although this invention may take many forms, prises the washer 54snfe'wed to the front beam `only two have been chosen-for illustration in 36, Yin combination withl 'a corresponding recess the drawings. Bothv forms include two front 58 in the front slat. When it is desired to slide legs or uprights 10, and two back legs .or upthe platform out of the way, it ismerely necesno rights 12. The legslOgarex pivoted to the topsary to raise the front slat clear of the washer 105 side members 14 which are rigidly secureclto and pushit back.r y the back legs v12 as by Ythe rivets 16. The top-l When it is desired to fold the ladder or to get sidemembers are composed of the two inner a step entirely out of the way, the step is shoved plates 18 andy the U-shaped member 20. To back partially off of the beam member as shown v y give the legs of the U the desired rigidity, its in Figure 2. To facilitate the movement of the 110 `ditio slats around the corner the beam members 34 are beveled at their back ends, and the back one of the slats 48 is beveled along its back-top edge. To hold the slats in position ready to be drawn up onto the beams, pairs of racks are provided. These racks comprise the guide members 62 (Figure 6) and the fillers 64 which position the slats endwise to'enter the recesses 46.

Although the top step 66 may be made in the same manner, a preferred embodiment has been shown. Here the slats 68 are permanently attached to the cross-members 70 which are pivoted at 72 to the back legs. When used as a step it is placed in the position shown in full lines in Figure 1, in which case its front end is supported by suitable plates or angle irons 74. The step may be swung over to the position shown in dotted lines to be used for a shelf, in which case it is held in horizontal position by the upper horizontal brace 31. Suitable means such as a spring friction member may be provided for holding the step in vertical position between the back legs when it is not wanted and particularly when the ladder is folded.

A suitable chain 79 is provided, connecting the upper and lower back beam members 34 so that both may be moved simultaneously. This should be connected near the bottom of the members so as not to interfere with closing the ladder.

To provide a suitable handle and toy further insure against twisting of the back legs an adcured across the forward edges of these legs.

To prevent undue wear, and especially elongation of the various pivot holes, suitable bushings and wear plates are preferably provided.

l For example, copper bushings are provided for the pivot holes at 40 and 42 where the front and back beammembers have their pivotal support.

'I'he operation of this ladder is as follows. To set up for use, the front and back legs are spread apart, and the beam members straightened down unless theymoved all the way down when the ladder was spread. The bottom platform (next tobottom step) is then pulled out and secured in its forward position. The secondplatform is left in its back position unless and until it is needed when it is pulled forward to the desired position. When the upper platform is back, the worker can have the use of the entire lower platform,-

so that he has a firm, safe anduntiring footing. The upper platform can be left in sort of a halfway position where it can be used if desired and 'yet is not much in the way. Unless the top step is wanted it is either left in its vertical position or it is turned back to be used as a shelf. To foldvthe ladder, the platforms are slid back beyond the hinges 38 and the two upper beams are broken by raising the central portions. This also breaks the lower beams,` as the upward movement is transmitted to them through the chain '79. By merely tilting the ladder it then collapses by its own weight. The bottom slats may be secured permanently in place by so spacing them that no slat lies across the joint between the two parts` of the beams, as shown in Figure 8.

It is thus seen that the ladder not only is more safe, satisfactory and eicient in use than any heretofore known but it is also as easily folded as any. Y l I claim:

1. A folding ladder including in a single active position four relatively hinged legs, folding beams between and pivotally mounted at their ends to said legs, a step slidably mounted on said beams,

vrear legs of the ladder l brace 80, or more if desired, may be se'-V lbeams and slidable to a position and a platform of more than six inches depth from front to back located asanother step below said slidable step; said slidably mounted step being guided from its customary useful position to an out-of-the-way position.

2. A folding ladder including a plurality of relatively hinged legs, a pair of folding beams between and pivotally mounted at their ends to said legs, a platform slidably mounted on said beams, and a rack into which said platform may be partially slid, said rack being mounted on the two adjacent said folding beams.

3. A folding ladder including a plurality of relatively hinged legs, a pair of folding beams between and pivotally mounted at their ends to said legs, a flexible platform slidably mounted on said beams, and a rack into which said platform may be partially slid, said rack being mounted on the two rear legs of the ladder adjacent their folding beams.

4. A folding ladder including a plurality of relatively hinged legs, a pair of folding beams between and pivotally mounted at their ends to said legs,'a platform slidably mounted on said beams, and a catch for preventing the accidental moving of said platform with, respect to said ladder.

'5. A folding ladder including a plurality of'relatively hinged legs, a pair of folding beams between and pivotally mounted at their ends to said legs, aplatform slidably mounted on said beams, and a projection on said beam, said platform be- .ing adapted to engage said projection and to be released therefrom by lifting upwardly.

lvatively hinged legs, an upper set and a lower set of folding beams -between and pivotally mounted at their ends to said legs, a platform permanently attached to the lower beams but so constructed and spaced as not to interfere with the folding of the beams, and a platform slidably mounted on the upper beams so that it can be slid out of the way of a person using the lower platform and to a position where it will not interfere with folding of the -upper set of beams.

7. A folding stepladder having relatively hinged legs and pairs of folding beams extending between said legs pivotally mounted at their ends to said legs at two elevations; a two-part platform supported by said lower beams, one part being permanently secured on each side of the folding joint; a platform slidably mounted on the upper across the folding joint in said beams and to a position entirely behind said joint; and a third platform above 130 said beams pivotally mounted to the rear legs of the ladder and movable to form a step within said ladder and alternatively a shelf behind said ladder.

8. A ladder including four legs relativelyA hinged y in pairs, a pair of folding beams between and pivotally mounted at their ends to said legs, and a step shiftably mounted on said beams, a platform of more than six inches depth from front to back located as another step below said shiftable step;

said shiftably mounted step being guided from its customary useful position to an out-of-the-way position.

9. A stepladder including a plurality of relatively hinged legs, two pairs of folding beams between and pivotally mounted at their ends to said legs, a platform of more than'eight inches depth from front to baok attached to the ladder and mounted on each pair of folding beams one above the other, the upper platform being shiftably 150 mounted on said beams and so constructed and guided that it may be moved from its usual operative position while the legs supporting it remain in theirlfully opened position to provide additional leg room above the lower platform.

l0. A folding multiple platform stepladder including a pair of front supporting legs and a pair of rear supporting legs, the pairs being relatively hinged at the top, and two platforms attached to and supported by said ladder one above the other each of a comfortable depth of more than about eight inches; the lower of said platforms being supported on a set of divided horizontal folding beams each pivotally mounted at its ends to a front leg and a rear leg of the ladder, and the upper of said platforms being supported jointly by said front and rear legs and shiftably mounted and so constructed that it may be moved from its usual operative position while the legs supporting it remain in their fully opened position; said platform being guided to such a position as to provide additional leg room above the lower platform.

11. A folding ladder including a plurality of relatively hinged legs, an upper set and a lower set of folding beams between and pivotally mounted at their ends to said legs, a platform permanently attached to the lower beams but so constructed and spaced as not to interfere with the folding of the beams, and a platform shiftably mounted on the upper beams so that it can be shifted and when shifted is guided to a position out of the way of a person using the lower platform and where it will not interfere with folding of the upper set of beams.

12. A folding, multiple platform stepladder including a pair of front supporting legs and a pair of rear supporting legs, the pairs being relatively hinged at the top, and two platforms supported by said ladder one above the other; each of saidvplatforms being supported by a pair of divided horizontal folding beams each pivotally mounted at its ends to a front and a rear leg of the ladder, and means connecting the upper beam and the lower beam, Said mean- Separation of said points to the distance at which.

they are located when the ladder is opened and the beams unfolded, and said means being so being attached to each beam near its point of folding and being so constructed as to limit the separation of said points to the distance at which they are located when the ladder is opened and the beams unfolded, and said means being sufficiently flexible to pertnit said points to move Closer together than the distance stated.

14. A stepladder having a plurality of legs, a plurality of steps secured at least indirectly to some of said legs and supported by some'of said legs and located one above another according to customary spacing; at least one of said steps other than the top step being in the form of a platform having a depth from front to back of over six inches, and the stepabove said platform being shiftable, independently of its verti- Cal supports, from its customary useful position above and slightly to the rear of the front of said platform, and being guided in its movement from said position to a position substantially back of said platform so that the space above said platform is substantially unobstructed by said step.

l5. A stepladder having a plurality of legs, a plurality of steps including upper steps and a lower step secured at least indirectly to some of said legs and supported by some of said legs and located one above another according to customary spacing; at least one of-said upper steps being shiftable1 independently of its vertical supports, from its customary useful position above and slightly to the rear of the front of said lower fstep, and being guided in its movement from said position to a position substantially further back Vso that a space deep from front to back above said lower step is substantially unobstructed by said upper step.

ALBERT A. SCHRAMM.

Images